Quartz is the most common crystal on earth and smoky quartz is a common type of quarts crystal. Smoky quartz has gray, brown or black “clouds” in the crystal. Sometimes the cloudiness is evenly distributed and sometimes it isn’t. I have seen some smoky quartz that is solid black. Exactly what causes the coloration is debatable, but it seems to be related to the amount and type of radiation the crystal is exposed to as it forms. Some colors of smoky quartz have been given alternate names. Morion is the solid black variety. Coon tail quartz is a variety that has alternating stripes of black and gray. Major sources of smoky quartz include Colorado and Brazil.
Folklore and healing properties:
Smoky quartz is reputed to relieve stress and reduce fear, anger and other negative emotions. It is believed to help in reaching goals. It aids creativity and setting priorities. It is said to improve fertility, aid in removing toxins from the body and aid the kidneys, adrenals, pancreas and sex organs. The brown colored crystals aid the lower chakras while the black is more neutral and can aid all of the chakras.